Comprehensive and Detailed Explanation From Exact Extract:

Perfusionrefers to delivery of oxygen and nutrients to tissues. It depends on three essential components:

Patent airway: Ensures oxygen reaches lungs

Intact microcirculation: Capillary-level exchange must function

Sufficient blood volume: Maintains blood pressure and oxygen transport

Hypoxic drive relates toCOPD physiology, not perfusion.High alveolar pressure(like from CPAP) mayimpede venous return, and alow ventilation-perfusion ratiomeans poor oxygenation efficiency, which negatively affects perfusion.